In the past, when a user of a vehicle parks his/her vehicle in a large-scale parking lot, there are cases in which the user forgets a parking position, and so an excessive time is taken until the user goes back to the parking position. For this reason, there have been proposed techniques of assisting the search of the parking position when the user goes back to the parking position.
For example, Patent Literature 1 discloses a technique by which a search of a parking position is assisted such that when a parking start of a vehicle is detected, an image of an area around the vehicle imaged by a camera mounted in the vehicle is transmitted to a portable terminal device carried by a user.
According to this technique, when the user goes back to the parking position, the transmitted image of the area around the vehicle is displayed on the portable terminal device, and it is possible to search for the parking position with reference to this image. Thus, it is possible to reduce a time taken until the user goes back to the parking position.